Structure of organic light-emitting TFT LCD and method of making the same

ABSTRACT

A structure of an organic light-emitting TFT LCD and the method for making the same are disclosed. The invention provides a glass substrate on which a TFT IC is formed. A metal layer forms the top layer of the TFT. Afterwards, a white light-emitting organic material layer is deposited thereon. A cover layer is then used to flatten the surface of the organic material layer. Finally, a photo mask pattern and a color filter plate are formed, completing the assembly of the TFT LCD.

BACKGROUND OF THE INVENTION

[0001] 1. Field of Invention

[0002] The invention relates to the structure of a TFT (Thin FilmTransistor) LCD (Liquid Crystal Display) and the method for making thesame. More particularly, the invention relates to the structure of anorganic light-emitting TFT LCD and the method for making the same.

[0003] 2. Related Art

[0004] The light-emitting methods in the existing TFT LCD's can beclassified as active and passive ones. Early light-emitting methods areall passive. A backlight source is used at the back of a glass substrateas the light source. A TFT IC (Integrated Circuit) on the glasssubstrate is used to control the liquid crystal layer between the glasssubstrate and a transparent conductive glass, so that the liquid crystallayer becomes transparent or opaque. Afterwards, the light passingthrough the liquid crystal layer is further filtered by color filterplates so that the emitted light can be red, green or blue. Throughsignal processing, light beams of three different colors are mixed toproduce colorful images. This kind of passive light-emitting methodsrequires the use of a backlight source and the opening of the LCD has tobe adjusted to obtain better light intensity.

[0005] With continuous researches and development in light-emittingmaterials, using light-emitting materials as the light sources of TFTLCD's becomes the trend in modem technologies. Using whitelight-emitting organic materials as the light source in the TFT LCD andusing the TFT to control the white light-emitting material or thedriving circuit for providing a voltage to the white light-emittingmaterial can easily control the bright spots on the LCD. Along withcolor filters as color modulating tools, the structure and manufacturingmethod for TFT LCD's can be greatly simplified.

[0006] Therefore, it is desirable to have a new structure of TFT LCD,which uses a white light-emitting organic material as the light sourceof the LCD and produces colorful images using the combination of a photomask pattern and color filters. Furthermore, a manufacturing method formaking the above-mentioned light source is proposed to more effectivelyassemble the LCD's.

SUMMARY OF THE INVENTION

[0007] The invention provides a structure of an organic material TFTLCD. The invention uses a white light-emitting organic material layer asthe light source of the LCD. A transparent conductive glass patternlayer and a mask pattern layer are directly formed on top of thelight-emitting layer. White light passes through color filters toproduce color spots.

[0008] The invention provides the structure of an organic TFT LCD. Theinvention uses a white light-emitting organic material layer as thelight source of the LCD. A cover layer is formed on the whitelight-emitting organic material layer to provide a planar surface. Atransparent conductive glass pattern layer is then directly formed onthe cover layer.

[0009] The invention provides the structure of an organic TFT LCD. Theinvention uses a white light-emitting organic material layer as thelight source of the LCD. A cover layer is formed on the transparentconductive glass pattern layer, and a photo mask pattern layer and colorfilters are directly formed on top of the cover layer.

[0010] The invention provides a manufacturing method for an organic TFTLCD. A TFT is directly covered with a metal layer. A whitelight-emitting organic material layer is then deposited on the metallayer and a glass substrate as the light-emitting layer of the LCD. TheTFT controls the light emission of the light-emitting material.

[0011] The invention provides a manufacturing method for an organic TFTLCD. A white light-emitting organic material layer is covered with aplanar film layer. The planar film layer is then directly formed with atransparent conductive glass pattern layer. This then completes theassembly of the LCD.

[0012] The invention provides a manufacturing method for an organic TFTLCD. A transparent conductive glass pattern layer is deposited with acover layer to obtain a planar surface, which is then covered with aphoto mask pattern layer and color filters.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] These and other features, aspects and advantages of the inventionwill become apparent by reference to the following description andaccompanying drawings which are given by way of illustration only, andthus are not limitative of the invention, and wherein:

[0014]FIG. 1 is a schematic cross-sectional view of the disclosed LCD,where a glass substrate is formed with a TFT IC that is further coveredby a metal material;

[0015]FIG. 2 is a schematic cross-sectional view of the disclosed LCD,where the TFT IC is covered with an organic white-light diode and a filmlayer is used to perform planarization process on the organicwhite-light diode;

[0016]FIG. 3 is a schematic cross-sectional view of the disclosed LCD,where a film layer is formed with a transparent conductive glass layerthat is aligned with the TFT IC;

[0017]FIG. 4A is a schematic cross-sectional view of the LCD structurein a first embodiment of the invention, where a mask pattern is formedat the opening of a conductive transparent glass layer as the mask layerbetween different color spots;

[0018]FIG. 4B is a schematic cross-sectional view of the LCD structurein a first embodiment of the invention, where between a transparentconductive glass layer and a mask pattern is formed in order a redfilter, a green filter, and a blue filter to modulate the color of lightcoming out of an organic white-light LED;

[0019]FIG. 5A is a schematic cross-sectional view of the LCD structurein a second embodiment of the invention, where a transparent conductiveglass layer is covered with a planar film layer to perform planarizationon the transparent conductive glass layer; and

[0020]FIG. 5B is a schematic cross-sectional view of the LCD structurein a second embodiment of the invention, where a planar film layer isformed with a mask pattern layer as the barrier between different colorspots, and a red filter, a green filter and a blue filter are formed inorder for modulating the white light emitted from an organic white-lightLED.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0021] This specification discloses a TFT (Thin Film Transistor) LCD(Liquid Crystal Display) structure with an organic light-emittingmaterial. The structure contains a glass substrate as the base of theTFT LCD. The glass substrate is formed with a TFT IC (IntegratedCircuit) as the control circuit of the LCD. A metal layer is formed onthe top surface of the TFT's. Afterwards, a white light-emitting organicmaterial layer is covers the metal layer and the glass substrate as thelight source of the LCD. A first cover layer covers the whitelight-emitting material layer, forming a planar surface. A transparentconductive glass pattern layer is defined on the first cover layersurface. A mask pattern layer is directly formed at the opening of thetransparent conductive glass pattern layer. Alternatively, a secondcover layer can be deposited on the transparent conductive glass patternlayer and the first cover layer. A mask pattern layer is then defined onthe second cover layer above the transparent conductive glass patternlayer. Finally, color filters are formed on the top, each of the colorfilters corresponding to a TFT to provide a color spot.

[0022] The invention also discloses a manufacturing method for a TFT LCDwith an organic light-emitting material. A glass substrate is providedas the base of the LCD. A TFT IC is defined on the surface of the glasssubstrate. The top of the TFT's is covered by a metal layer as a metalconductive layer. Afterwards, a white light-emitting organic materiallayer is deposited on the metal layer and the glass substrate as thelight source of the LCD. A first cover layer is then deposited on thewhite light emitting organic material layer, forming a planarizedsurface. A transparent conductive glass pattern layer is subsequentlydefined on the surface of the first cover layer above the TFT's. Theopening of the transparent conductive glass pattern layer is formed witha mask pattern layer, or deposited with a second cover layer first,forming a planarized surface on the transparent conductive glass patternlayer, and then a mask pattern layer. According to the invention, themask pattern layer directly fills or covers the openings on thetransparent conductive glass pattern layer. Finally, color filtersconsisting of a red filter, a green filter, and a blue filter areformed. Each color filter corresponds to a TFT to control color spots.

[0023] In the following paragraphs, we use FIGS. 1 to 2 along with FIGS.4A and 4B to explain the first embodiment of the invention. Withreference to FIG. 1, a glass substrate 100 is provided as the base of aTFT LCD. The surface of the glass substrate 100 is then formed with aplurality of TFT's 120, forming a TFT IC as the control circuit of theLCD. The plurality of TFT's 120 partially covers the glass substrate100. In particular, the manufacturing method of the TFT's 120 is theusual semiconductor process.

[0024] With further reference to FIG. 1, a conductive metal material isdeposited on the TFT's 120 and the glass substrate 100. Thephotolithographic and etching technologies are employed to remove themetal material on the glass substrate 100, forming a metal layer 120 onthe TFT's 110. The TFT's 110 impose a voltage on the whitelight-emitting organic material of the LCD through the metal layer 120,thereby controlling the light emission of the white light-emittingorganic material.

[0025] As shown in FIG. 2, a white light-emitting organic material layer130 is formed on the metal layer 120 and the glass substrate 100 as thelight-emitting material of the LCD. The material of the whitelight-emitting organic material layer 130 is a white light LED(Light-Emitting Diode) organic material. When the TFT's 110 impose avoltage on this kind of material, white light is emitted. Afterdepositing the white light-emitting organic material layer 130, a firstcover layer 140 is deposited upon the white light-emitting organicmaterial layer 130, forming a planarized surface. According to apreferred embodiment, the first cover layer 140 consists of Polyimide,Acrylize, or transparent photoresist to achieve the planarization. Inyet another embodiment of the invention, the first cover layer 140consists of silicon nitride. After the silicon nitride is deposited onthe white light-emitting organic material layer 130, a CMP (ChemicalMachine Polishing) is employed to planarize the silicon nitride toobtain a flat surface for subsequent processes.

[0026] With reference to FIG. 3, a transparent conductive glass isdeposited on top of the first cover layer 140. Afterwards, thephotolithographic and etching technologies are employed to remove thetransparent conductive glass that is not on the TFT's 110, forming atransparent conductive glass pattern layer 150. The transparentconductive glass pattern layer 150 is aligned with the TFT's 110. Whenthe TFT's 110 impose a voltage through the metal layer 120 on the whitelight-emitting conductive material layer 140, the white light passesthrough the transparent conductive glass pattern layer 150 and reachescolor filters. In the invention, the transparent conductive glasspattern layer 150 can connect to another electrode of the whitelight-emitting organic material layer 140 to finish the circuitconnection.

[0027] As shown in FIG. 4A, a photo mask material is deposited on thefirst cover layer 140 and the transparent conductive glass pattern layer150. The photolithographic and etching technologies are employed toremove the photo mask material on the transparent conductive glasspattern layer 150, forming a mask pattern layer 160. The mask patternlayer 160 fills the openings in the transparent conductive glass patternlayer 150, defining the bright positions of the LCD and avoiding themixture of spots with different colors.

[0028] With reference to FIG. 4B, color filters 170 are formed on themask pattern layer 160 and the transparent conductive glass patternlayer 150. When the whit light-emitting organic material layer 130 sendsout white light, it passes through the transparent conductive glasspattern layer 150 and reaches the color filters 170. The white light isconverted into red, blue and green light here. The intensities ofdifferent colors are modulated to make desired color images. The colorfilters 170 consist of a red filter, a green filter, and a blue filterarranged in order on the mask pattern layer 160 and the transparentconductive glass pattern layer. Each TFT 110 corresponds to one of thecolor filters (red, green or blue).

[0029] We will use FIGS. 1 through 3 along with FIGS. 5A and 5B toexplain a second embodiment of the invention. As shown in FIGS. 1through 3, a glass substrate 100 is formed with TFT's 110, on top ofwhich is formed with a metal layer 120. Afterwards, a whitelight-emitting organic material layer 130 and a first cover layer 140are deposited and the surface of the first cover layer 140 is definedwith a transparent conductive glass pattern layer 150. The details arethe same as in the first embodiment and therefore are not repeatedherein.

[0030] With reference to FIG. 5A, after defining the transparentconductive glass pattern layer 150 a second cover layer 155 is depositedon the transparent conductive glass pattern layer 150 and the firstcover layer 140, forming a planarized surface. In a preferred embodimentof the invention, the second cover layer 155 consists of Polyimide,Acrylize, or transparent photoresist. In another embodiment, the secondcover layer 155 uses silicon nitride. After the silicon nitride isdeposited, a CMP (Chemical Machine Polishing) is employed to planarizethe silicon nitride to obtain a flat surface for subsequent processes.

[0031] As shown in FIG. 5B, a photo mask material is deposited on thesecond cover layer 155. The photolithographic and etching technologiesare then employed to remove the photo mask material, forming a maskpattern layer 160 on the second cover layer 155. The mask pattern layer160 is formed on the openings of the transparent conductive glasspattern layer 150, without blocking the white light emitted out of thetransparent conductive glass pattern layer 150. Once the mask patternlayer 160 is defined, color filters 170 are formed on top of the maskpattern layer 160 and the second cover layer 155. The color filters 170consist of a red filter, a green filter, and a blue filter arranged inorder on the second cover layer 155. Each TFT 110 is aligned with one ofthe color filters (red, green or blue) so that each TFT 110 produces acolor spot.

[0032] Although the invention has been described with reference tospecific embodiments, this description is not meant to be construed in alimiting sense. Various modifications of the disclosed embodiments, aswell as alternative embodiments, will be apparent to persons skilled inthe art. It is, therefore, contemplated that the appended claims willcover all modifications that fall within the true scope of theinvention.

What is claimed is:
 1. A structure of the TFT (Thin Film Transistor) LCD (Liquid Crystal Display) with an organic light-emitting material, which comprises: a glass substrate; a plurality of TFT's formed on the top surface of the glass substrate as the control circuit of the LCD; a metal layer covering the top surface of the plurality of TFT's; a white light-emitting organic material layer covering the metal layer and the glass substrate; a cover layer formed on the white light-emitting organic material layer to form a planarized film layer; a transparent conductive glass pattern layer formed on the cover layer to cover the plurality of TFT's only; a mask pattern layer formed on the cover layer and filling the openings on the transparent conductive glass layer; and color filters formed on the transparent conductive glass pattern layer and the mask pattern layer for performing color modulations on the white light emitted by the white light-emitting organic material layer.
 2. The LCD structure of claim 1, wherein the metal layer consists of a conductive metal material.
 3. The LCD structure of claim 1, wherein the white light-emitting organic material is a white LED (Light-Emitting Diode) organic material.
 4. The LCD structure of claim 1, wherein the cover layer consists of a material selected from the group consisting of Polyimide, Acrylize and transparent photoresist.
 5. The LCD structure of claim 1, wherein the cover layer consists of silicon nitride and its surface is planarized through a CMP (Chemical Machine Polishing).
 6. The LCD structure of claim 1, wherein the transparent conductive glass layer consists of ITO.
 7. The LCD structure of claim 1, wherein the color filters consist of a red filter, a green filter, and a blue filter.
 8. A structure of the TFT LCD with an organic light-emitting material, which comprises: a glass substrate; a plurality of TFT's formed on the top surface of the glass substrate as the control circuit of the LCD; a metal layer covering the top surface of the plurality of TFT's; a white light-emitting organic material layer covering the metal layer and the glass substrate; a first cover layer formed on the white light-emitting organic material layer to form a planarized film layer; a transparent conductive glass pattern layer formed on the cover layer to cover the plurality of TFT's only; a second cover layer formed on the first cover layer and the transparent conductive glass layer; a mask pattern layer formed on the second cover layer; and color filters formed on the second cover layer and the mask pattern layer for performing color modulations on the white light emitted by the white light-emitting organic material layer.
 9. The LCD structure of claim 8, wherein the metal layer consists of a conductive metal material.
 10. The LCD structure of claim 8, wherein the white light-emitting organic material is a white LED (Light-Emitting Diode) organic material.
 11. The LCD structure of claim 8, wherein the first cover layer consists of a material selected from the group consisting of Polyimide, Acrylize and transparent photoresist.
 12. The LCD structure of claim 8, wherein the first cover layer consists of silicon nitride and its surface is planarized through a CMP (Chemical Machine Polishing).
 13. The LCD structure of claim 8, wherein the transparent conductive glass layer consists of ITO.
 14. The LCD structure of claim 8, wherein the second cover layer consists of a material selected from the group consisting of Polyimide, Acrylize and transparent photoresist.
 15. The LCD structure of claim 8, wherein the second cover layer consists of silicon nitride and its surface is planarized through a CMP (Chemical Machine Polishing).
 16. The LCD structure of claim 8, wherein the color filters consist of a red filter, a green filter, and a blue filter.
 17. A manufacturing method of the TFT LCD with an organic light-emitting material, which comprises the steps of: providing a glass substrate; forming a plurality of TFT's on the top surface of the glass substrate as the control circuit of the LCD; forming a metal layer on the top surface of the plurality of TFT's; depositing a white light-emitting organic material layer on the metal layer and the glass substrate; forming a cover layer on the white light-emitting organic material layer to form a planarized film layer; defining a transparent conductive glass pattern layer formed on the cover layer to cover the plurality of TFT's only; defining a mask pattern layer, filling the openings on the transparent conductive glass pattern layer; and forming color filters on the cover layer and the mask pattern layer for performing color modulations on the white light emitted by the white light-emitting organic material layer.
 18. The method of claim 17, wherein the metal layer consists of a conductive metal material.
 19. The method of claim 17, wherein the white light-emitting organic material is a white LED (Light-Emitting Diode) organic material.
 20. The method of claim 17, wherein the cover layer consists of a material selected from the group consisting of Polyimide, Acrylize and transparent photoresist.
 21. The method of claim 17, wherein the cover layer consists of silicon nitride and its surface is planarized through a CMP (Chemical Machine Polishing).
 22. The method of claim 17, wherein the transparent conductive glass layer consists of ITO.
 23. The method of claim 17, wherein the color filters consist of a red filter, a green filter, and a blue filter.
 24. A manufacturing method of the TFT LCD with an organic light-emitting material, which comprises the steps of: forming a glass substrate; forming a plurality of TFT's on the top surface of the glass substrate as the control circuit of the LCD; forming a metal layer on the top surface of the plurality of TFT's; depositing a white light-emitting organic material layer on the metal layer and the glass substrate; forming a first cover layer on the white light-emitting organic material layer to form a planarized film layer; defining a transparent conductive glass pattern layer on the cover layer to cover the plurality of TFT's only; forming a second cover layer on the first cover layer and the transparent conductive glass layer; defining a mask pattern layer on the second cover layer; and forming color filters on the second cover layer and the mask pattern layer for performing color modulations on the white light emitted by the white light-emitting organic material layer.
 25. The method of claim 24, wherein the metal layer consists of a conductive metal material.
 26. The method of claim 24, wherein the white light-emitting organic material is a white LED (Light-Emitting Diode) organic material.
 27. The method of claim 24, wherein the first cover layer consists of a material selected from the group consisting of Polyimide, Acrylize and transparent photoresist.
 28. The method of claim 24, wherein the first cover layer consists of silicon nitride and its surface is planarized through a CMP (Chemical Machine Polishing).
 29. The method of claim 24, wherein the transparent conductive glass layer consists of ITO.
 30. The method of claim 24, wherein the second cover layer consists of a material selected from the group consisting of Polyimide, Acrylize and transparent photoresist.
 31. The method of claim 24, wherein the second cover layer consists of silicon nitride and its surface is planarized through a CMP (Chemical Machine Polishing).
 32. The method of claim 24, wherein the color filters consist of a red filter, a green filter, and a blue filter. 